The invention relates to conducting polymer films and, more particularly, to conductive polymer films grown on metal substrates.
The development of electrically conducting polymers, such as polyaniline and polypyrrole, has advantageously provided coatings that can extend the applications of conductive metal and semiconductive substrates to environments that are harmful to these materials. However, it can be difficult to form a conducting polymer film with the desired adhesion and density on the substrate surface.
For semiconductor surfaces, conducting polymers are attached by modifying the semiconductor surface with a coupling reagent so that the polymer can covalently or coordinatively bond to the semiconductor surface. This process is set out in U.S. Pat. No. 4,476,003, "Chemical Anchoring of Organic Conducting Polymers to Semiconducting Surfaces," issued 10/9/84, to Frank et al. The resulting film provides a barrier to direct photodegradation or chemical degradation of the semiconductor substrate.
Conducting polymer films grown on metal substrate surfaces have generally been of low density, with concomitant relatively low electronic conductivity and/or low adhesion to the surface. Accordingly, it is an object of the present invention to provide an electrochemically grown conducting polymer film with improved adhesion and morphology on a metal substrate.
Another object of the invention is to provide a conducting polymer film with a high density on a metal substrate.
One other object is to increase the adhesion between the film and the metal substrate.
Additional objects, advantages and novel features of the invention will be set forth in part in the description which follows, and in part will become apparent to those skilled in the art upon examination of the following or may be learned by practice of the invention. The objects and advantages of the invention may be realized and attained by means of the instrumentalities and combinations particularly pointed out in the appended claims.